Previously prepped - A. Kong, S. Liu, A. Tam

• Gate valve assembly put together
•  All bolts torqued to >=55Nm
• Gate valve Cart moved into hotcell

April 23, 2025 - A. Kong, C. Fisher, S. Liu, M. Genix, A. Tam 

• Moved standoffs to the taller position on the cart
• Weight added to cart to bring CG towards centre of cart.
  • Cart rolling away and hitting lip of lift table could tip (especially with gate valve in higher position)
• Gate valve moved onto cart via 1000kg crane
  • Sling used between openings in gate valve assembly frame members
• Complete gate valve assembly with hard stop and bellows movement retainer
• Dust cover removed, sealing (o-ring) flange removed,
• vacuum and sealing surfaces cleaned,
• hard stops (gate valve – shield plug) installed, bellows limit brackets installed
• Bagged all items removed to keep them clean
  

QDS seal installed BY HAND onto gate valve tapered flange

• Seal tabs align with a cutout feature on the flange (3 tabs, 120O spacing @ 10:00, 2:00, 6:00)
• These cutouts allow the tabs to bend towards the flange without obstructing sealing surfaces

RH Assumptions (UNTESTED)

• in the situation of a gate valve assembly replacement:
  • Seal should be pre-installed onto gate valve flange using soft jawed clamps (bought, designed, modified)
  • Assembly should come bagged and bag removed at the point of installation to reduce contamination on  vacuum and sealing surfaces
• if seal replacement on its own (eg. during extraction electrode replacement)
  • Seal should arrive on a clean stand through tool port and oriented in installation position
  • two manips to place seal onto flange; grabbing top two tabs (UNTESTED but confident because of taper on seal retainer)
  • clamps are TBD (bought, designed, modified)               

Installing gate valve assembly proposed sequence of operations:

• Using Hotcell lift table, raise gate valve assembly so that Shield-plug-to-gate-valve screw can engage, leaving ~1/8 inch between Shield-plug and gate-valve-assembly
• Slide gate-valve with cart into rough x-y position (use camera views for alignment)
• Start thread on shield-plug-to-gate-valve screw, until weight is released from cart.
• Release gate valve from cart by unscrewing 2 bolts holding it
• Torque shield-plug-to-gate-valve screw fully to align hard-stop threaded holes
• Lightly install hard-stop screws
• Crack loosen the shield plug-gate valve screws
• Final torque on hardstop screws
• Final torque on shield plug-gate valve screws

Additional Notes:

• Tested manipulator access/reach to the hard-stop screws)
  • (better access may be achieved by lowering torque tool handle)
• Nut housing for shield plug to gate valve assembly screws/nuts not used as final bolts will react differently than test shield-plug

To be tested:

• Gate valve seal clamping using torque multiplier and reaction arm.